Navegando por Assunto "Morfologia animal"

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Caracterização morfológica de Liophis reginae semilineatus (Wagler, 1824) e Liophis reginae macrosomus (Amaral, 1935), e o status taxonômico de Liophis oligolepis Boulenger, 1905
(Universidade Federal do Pará, 2002-10-25) COSTA, Robson Gil Neris; PRUDENTE, Ana Lúcia da Costa; http://lattes.cnpq.br/1008924786363328
The Brazilian subspecies of Liophis reginae (Liophis reginae macrosomus and Liophis reginae semilineatus) were analyzed, in order to characterize the two taxa and to verify the validity of Liophis oligolepis, considered a synonym of Liophis regime semilineatus. External morphology, cranial osteology and hemipenis were examined. Based on a MANOVA, significant sexual differences in head and body variables were identified. A discriminant analysis function (DAF) was performed for males and females separately, in order to maximize in a multivariate space the differences between the three previously defined taxa: Liophis reginae semilineatus, Liophis reginae macrosomus, and Liophis oligolepis. The first discriminant component in males separated clearly Liophis reginae semilineatus and Liophis oligolepis, while Liophis reginae semilineatus and Liophis reginae macrosomus separated at the second discriminant component. In females, the first disctiminant component separated Liophis oligolepis from Liophis reginae semilineatus and Liophis reginae macrosomus. When both sexes were analysed together, for the pairs of taxa Liophis oligolepis - Liophis reginae semilineatus, and Liophis reginae semilineatus - Liophis reginae macrosomus, both pairs were separated by the first discriminant component. Since some specimens of Liophis reginae semilineatus and Liophis reginae macrosomus were registered beyond their previous known distribution, a DAF was applied to verify if these specimens grouped within their presumed taxa or geographically. The first possibility occurred, supporting the validity of each taxon and raising the question of their taxonomic status. The hemipenian morphology does not differ between Liophis reginae semilineatus, Liophis reginae oligolepis and Liophis reginae macrosomus. The three taxa present similar skulls, although differences were observed between the parietal bones of Liophis reginae semilineatus and Liophis reginae oligolepts. The validity of Liophis oligolepis was corroborated, based on meristic, morphometric and morphological characters. Future studies will be necessary to test the Liophis reginae semilineatus and Liophis reginae macrosomus status.
Acesso aberto (Open Access)
Diversidade morfológica e molecular do gênero Oecomys thomas, 1906 (Rodentia: Cricetidae) na Amazônia oriental brasileira
(Universidade Federal do Pará, 2010) FLORES, Tamara Almeida; SILVA JÚNIOR, José de Sousa e; http://lattes.cnpq.br/4998536658557008; ROSSI, Rogério Vieira; http://lattes.cnpq.br/0447251112059340
The arboreal rice rats, genus Oecomys, are distributed in tropical and subtropical areas from Central and South America, with 17 currently recognized species and another two species already described in earlier studies but still unnamed. Six of these species are expected to occur in eastern Brazilian Amazon. Because defining the species limits inside Oecomys based only on morphological characters is a complicated task, many nominal taxa have already been associated to the genus, and different taxonomic arrangements have been proposed by specialists. Despite of this taxonomic instability, there is only one taxonomic review for the genus carried out 50 years ago, in which only two polytypical species were recognized. However, several recent studies based on morphological, molecular and karyotypical data have been showing that the species diversity inside Oecomys is largely underestimated, resulting in recent descriptions of new taxa or revalidation of previously synonymized species. This work aimed to assess the species diversity inside this genus in the eastern Brazilian Amazon by investigating the molecular and morphological variation in regional specimens. We employed phylogenetic analysis based on cytochrome-b in order to define clades that may represent species, and described the external and cranial morphology of these recognized species. As a result, we recognized 11 species in the eastern Amazonian forest in Brazil, of which five are already expected to occur in this area (Oecomys auyantepui, O. bicolor, O. paricola, O. rex, and O. rutilus), two are recorded for the first time in the biome Amazonia (Oecomys catherinae and O. cleberi), and the four are either new or not currently recognized species (i.e. synonyms), herein referred as Oecomys sp. A, Oecomys sp. B, Oecomys sp. C, and Oecomys sp. D. Moreover, we suggest that Oecomys bicolor is a species complex, based in the high nucleotide divergence we found (7.5 %), corroborating previous molecular studies. We observed sexual dimorphism and ontogenetic variation on cranial morphometry in the species Oecomys paricola, and for comparison purposes we treated all other species herein studied as exhibiting this kind of dimorphism. We also suggest a phylogenetic hypothesis among the species of this genus based on 653 bp of cytochrome-b. This is the most comprehensive phylogeny for Oecomys published to date, due to the great number of species included in the analysis (11 of the 16 currently recognized species plus seven probably new species), and the wide-ranging geographic area included in our sample.
Acesso aberto (Open Access)
Efeito das paisagens modificadas por práticas agrícolas sobre a composição e estrutura das assembléias e espécies de Drosophilidae (Diptera)
(Universidade Federal do Pará, 2014-11-28) FURTADO, Ivaneide da Silva; MARTINS, Marlúcia Bonifácio; http://lattes.cnpq.br/8882047165338427
The Amazon Rainforest holds the largest biodiversity in the world. It occupies more than 40% of the Brazilian surface. In recent years the rates of forest loss and degradation of Amazonia have considerably increased as a result of agricultural expansion, creating a mosaic of highly modified landscapes. These changes endanger both biodiversity and ecosystem services associated with it, besides causing severe stress on the species. Effects of stress can result in physiological changes that are reflected in morphological differentiation among remnant populations, which now occupy the new landscape. The objective of this study was to test the effect of some types of land use on the assembly of frugivorous Drosophilidae and on the morphology of some species originally settled within the forest areas that have become a patchwork landscape containing forest fragments, ecological succession and crop zones. The first study was conducted in three agricultural villages and the second within six locations, including three preserved forest areas. Sampling was performed in a standardized manner, with traps placed along the established transects on the use of predominant land within the area of study. Our results showed that the richness of the species did not differ between different types of land use, but the distributions and abundances of the species' composition were clearly distinct between intensive agricultural uses and forest systems. The forest's coverage and the relative humidity were the variables determining the distribution of the species. The agricultural uses were characterized by cosmopolitan non-native species associated with more open areas. There were found morphological differences between the individuals caught in the areas of preserved forest and agricultural use zones, regardless of the species. Surprisingly, the number of individuals captured in the forests was always lower compared to those captured in the more intensive types of use. These results show the effects of landscape mutation on the remaining populations of native species, indicating the range of quantitative and qualitative alterations on the set of species. However, the maintenance of the forest patches on areas of agricultural use can benefit the permanency of native species in these landscapes.
Acesso aberto (Open Access)
Estudo estrutural e ultra-estrutural das gônadas masculinas dos diferentes morfotipos de Macrobrachium amazonicum.(Heller, 1862) (Crustacea, Decapoda, Palaemonidae)
(Universidade Federal do Pará, 2006) SILVA, Gicelle Maria Farias da; ROCHA, Rossineide Martins da; http://lattes.cnpq.br/4371300451793081
Macrobrachium amazonicum is the most commercially-explored fresh water shrimp in the Amazon, finding great acceptance in the consuming market. The objective of this work is to characterize the structure and the ultrastructure of the gonads of different M. amazonicum morfotipos in natural population. The shrimps (500 specimen) were collected in Furo das Marinhas (Mosqueiro – PA), by local fishermen and brought alive to the Laboratório, in an appropriate box containing local water. Fifty males were selected, weight, measured and killed. Gonads were collected and fragments were fixed in 2,5% glutaraldehyde 4% paraformaldehyde in sodium caccodylate buffer at 0,1M pH 7,2. For light microscopy the fragments were processed according to the standard histological technique for paraffin embedding. The sections were stained with Hematoxilin and Eosin. For transmission electron microscopy the gonads were post-fixed with 1% osmium tetroxide in sodium caccodylate buffer at 0,1M pH 7,2 and processed for embedding in Epon resin. Semithin sections were stained with toluidin blue. For scanning electron microscopy the fixed and post-fixed specimens were dehydrated, submitted to the critical CO2 drying point and then coated with gold and examined in electron microscope. Four morfotips in natural population were observed, in agreement with corporal dimensions and coloration. The morfotips were denominated as TC, CC, GC and GC’ according to Moraes-Riodades (2002). The biometric relation total/length cephalothorax and total/weight had presented negative allometrie.The testicles and are located in the cephalothorax. The testicle is constituted by seminiferous tubules; each tubule presents a very thin capsule of conjunctive tissue that divides the parenquime of the organ. The tubule is covered by flat cells and in its interior we observed a cell population of spermatogenic lineage in different maturation phases that were denominated as: spermatogônias, spermatocytes, spermatids and spermatozoids. The spermatogonias are the largest cells with cromatina organized in clots, located eccentrically in the tubule. The spermatocytes are round cells with cromatina in dense clots. The spermatids are small cells with great amounts of mitochondria. The spermatozoids are concave cells in the apical portion and convex cells in the distal portion, presenting a small spike assuming an aspect similar to a cup. In cross section, the vas deferens come covered by conjunctive tissue and they can present from a cubic to a cylindrical epithelium; they present in their interior an agglomeration of feeder cells located in the eccentric portion and spermatozoids located in the lumen of the ducts.The structural analysis of the M. amazonicum gonads, demonstated the of three distinct morfotips in the Furo das Marinhas.
Acesso aberto (Open Access)
Estudo morfofisiológico do epidídimo de caititus (Pecari tajacu) adultos
(Universidade Federal do Pará, 2015-05-28) OLIVEIRA, Anna Patrycia Martins de; GUIMARÃES, Diva Anelie de Araújo; http://lattes.cnpq.br/2891287458034896
This work aimed to study the histology of epididymis peccaries (Pecari tajacu) and sperm pathologies associated with different regions of the organ. A fact that will contribute to a better understanding of the reproductive biology of the species, and consequently for their conservation. Eight adult animals were used, aged two to four years, coming from breeding scientific research of Embrapa Amazônia Oriental, located in Belém, Pará, Brazil. Each of the four parts of the epididymis (proximal the head and distal the head, body and tail) was divided into two portions, and one of the portions was macerated, while the other remained intact. The epididymal tail underwent retrograde flow technique. The cell samples were stored in formol saline, and then used for the analysis of sperm morphology. Samples of the body were wrapped in gauze, identified and fixed in ALFAC. Later, they were submitted to routine histological processing. Diameters were measured up to 20 tubules and the heights of up to 30 tubules epithelium, the epididymis of each region for each animal. ANOVA (One Way), pointed out differences between the diameter of the proximal tubule of the head and distal head (p = 0.0008); between the proximal head and the body (p = 0.0009); between the proximal head and the tail (p = 0.0002). There were no significant differences (p> 0.05) among the other parts of the epididymis. It was found that the proximal head has a diameter of less tubules average compared to other portions of the epididymis. The Newman Keuls test showed similarities between the average body epithelium height and tail (p = 0.551). However, significant differences were observed between the distal head and the proximal head (p = 0.0009); the distal head and the tail (p = 0.0055); distal head and body (p = 0.0021); proximal head and body (p = 0.0008); proximal head and tail (p = 0.0055). In all regions of the epididymis of peccary, it observed the presence of pseudostratified columnar epithelium with stereocilia. 13 different types of morphological changes were found, and underdeveloped sperm and loose heads were the most frequent along the epididymis of peccaries. There were no differences in the number of pathologies in different regions of the epididymis (Man-Whitney test) (proximal head: U = 19.500, p = 0.189; distal head: U = 31.500, p = 0.958; body: U = 27,000; p = 0.599 and tail: U = 20.000, p = 0.207). In many species the histopathological analysis are often studied, however in wild animals, such as peccary, are still poorly researched. Thus, this study data are pioneers, and will serve as a basis for future comparative research on the reproductive biology of artiodactyls, contributing to their conservation and production.
Acesso aberto (Open Access)
Fauna microparasitária de Brachyplatystoma rousseauxii e Mugil curema desembarcados na Amazônia oriental
(Universidade Federal do Pará, 2013-11-29) DIAS, Lilian de Nazaré Santos; MATOS, Edilson Rodrigues; http://lattes.cnpq.br/7895814591867510; PAIVA, Rosildo Santos; http://lattes.cnpq.br/0510818763187669; FREITAS, José de Arimatéa; http://lattes.cnpq.br/2382745365421156
The gilthead bream Brachyplatystoma rousseauxii and white mullet Mugil curema are species of fish consumption and considerable commercial value found in estuarine cost of Pará The microparasites phyla Apicomplexa, Microspora and Myxozoa are organisms that can be found parasitizing vertebrates and invertebrates, including the fish, some pathogenic potential and even zoonotic and economic impact. To discover the fauna microparasites affecting fish , 62 specimens of B. rousseauxii and 58 M. curema estuarna captured on the coast of the city of Vigia de Nazare and Mosqueiro District, in Belem, Para state were examined as methods and techniques for morphological analysis (microscopy light), ultrastructural (transmission electron microscopy, TEM) and molecular biology (phylogenetic analysis). It was observed that there are three phyla (three in B. rousseauxii and two in M. curema) captured hosts in the two locations , plus the largest parasitic index was determined in specimens of both captured on the coast of the estuarine Vigia de Nazare , higher incidence of co microparasites phyla Apicomplexa and Myxozoa, beyond multiparasitism in B. rousseauxii Morphological analysis revealed the presence of Calyptospora sp. (Apicomplexa), Ellipsomyxa sp., Henneguya sp., Myxobolus sp. and Meglishcha sp. (Myxozoa) and Kabatana sp. (Microspora) in B. rousseauxii and Ellipsomyxa sp., Myxobolus sp. and Microspora phylum microparasito in M. curema. The data analysis of morphological and ultrastructural Myxospora found in B. rousseauxii and M. curema are suggestive of new species microparasites these two hosts. Phylogenetic analysis of the data did not provide results that allow the classification of Kabatana sp. (Microspora) and Henneguya sp. (Myxozoa) found parasitizing B. rousseauxii microparasites as new species in this host due to low bootstrap value, but by analyzing the distance p was possible to suggest that these are new species. Studies about microparasites in Amazonian fish are needed for the knowledge of the occurrences, characterization d new species, the pathogenic potential hosts and possible risk to the consumer.
Acesso aberto (Open Access)
Revisão taxonômica do complexo Micrurus spixii Wagler, 1824 (Serpentes, Elapidae)
(Universidade Federal do Pará, 2016-03-31) NASCIMENTO, Lywouty Reymond de Souza; PRUDENTE, Ana Lúcia da Costa; http://lattes.cnpq.br/1008924786363328